Second-hand smoke exposure (SHSe) is unequivocally harmful to children's health as evidenced by increased rates of asthma, bronchiolitis, and respiratory infections. Up to 48% of children who visit the pediatric emergency department (PED) are exposed to SHS. Our research has shown that tobacco interventions are feasible and effective in the PED setting. However, PED nurses (RNs) do not deliver SHSe counseling in a systematic way due to barriers such as lack of training, time, and structured systems. The Clinical Practice Guidelines for Treating Tobacco Use and Dependence (CPGs) recommends that pediatric practitioners treat adult caregivers who smoke in all clinical encounters by using: 1) electronic medical records (EMR) to document tobacco use and SHSe, 2) prompts within a decision support system (DSS) to promote cessation counseling and urge all smokers to quit, and 3) advice to all smokers that the only effective protection from SHSe is to make their homes and cars smoke-free. The expanded use of the EMR to prompt RNs to treat tobacco dependence and provide feedback has been used successfully in adult settings, and provides a means to standardize screening and counseling of adult tobacco users in the PED. However, DSS tools designed to facilitate SHSe reduction have not been developed for use in the PED. We propose a study that will be the first to develop and evaluate a PED DSS-EMR System to facilitate the identification of smokers and the delivery of a SHSe intervention to caregivers who bring their child to the PED. We will conduct a two- phased project to develop, refine, and integrate an Epic-based DSS, using the CPGs, our prior PED cessation work, and our effective web-based cessation training program. In Phase I, we will develop a three-part DSS with prompts to: 1) ASK about child SHSe and caregiver smoking using the same screening prompts required by the Meaningful Use incentive program, 2) Use a free software program (REDCap) to ADVISE caregivers to reduce their child's SHSe via total smoking home and car bans and quitting smoking, and 3) ASSIST caregivers to quit by directly connecting them to their choice of free cessation resources (e.g., Quit- line, txt2quit, smokefree.gov) during the PED visit. We will create reports to provide feedback to RNs on their SHSe counseling behaviors. RNs will provide input on program content, functions, and design. In Phase II, we will conduct a 3-month feasibility trial to test the results of implementing our DSS on changes in RN SHSe-related behaviors, and child and caregiver outcomes. If effective, program results, procedures, and REDCap templates will be disseminated easily. The DSS will use a system of prompts and templates that can be modified, shared and used in all emergency settings (e.g., pediatric or adult), regardless of EMR type. Compliance and interest in the DSS will be increased by incorporating the widely-used Meaningful Use tobacco recording requirements, further increasing relevance to other institutions. This systems-based approach has the potential to reach at least 12 million smokers a year and significantly reduce SHSe-related pediatric illnesses and related costs.